[ELF] Fix -exclude_libs option

elf/cmdline.cc

@@ -796,6 +796,8 @@ void parse_nonpositional_args(Context<E> &ctx,
   if (ctx.arg.output.empty())
     ctx.arg.output = "a.out";
 
+  ctx.arg.undefined.push_back(ctx.arg.entry);
+
   // TLSDESC relocs must be always relaxed for statically-linked
   // executables even if -no-relax is given. It is because a
   // statically-linked executable doesn't contain a tranpoline

elf/object-file.cc

@@ -888,7 +888,11 @@ ObjectFile<E>::mark_live_objects(Context<E> &ctx,
   for (i64 i = first_global; i < this->symbols.size(); i++) {
     const ElfSym<E> &esym = elf_syms[i];
     Symbol<E> &sym = *this->symbols[i];
-    merge_visibility(ctx, sym, exclude_libs ? STV_HIDDEN : esym.st_visibility);
+
+    u8 visibility = esym.st_visibility;
+    if (esym.is_defined() && exclude_libs)
+      visibility = STV_HIDDEN;
+    merge_visibility(ctx, sym, visibility);
 
     if (sym.traced) {
       if (esym.is_defined())

test/elf/exclude-libs3.sh

@@ -0,0 +1,26 @@
+#!/bin/bash
+set -e
+cd $(dirname $0)
+mold=`pwd`/../../mold
+echo -n "Testing $(basename -s .sh $0) ... "
+t=$(pwd)/../../out/test/elf/$(basename -s .sh $0)
+mkdir -p $t
+
+cat <<EOF | clang -xc -c -o $t/a.o -
+void foo();
+void bar() { foo(); }
+EOF
+
+rm -f $t/b.a
+ar crs $t/b.a $t/a.o
+
+cat <<EOF | clang -xc -c -o $t/c.o -
+void bar();
+void foo() { bar(); }
+EOF
+
+clang -fuse-ld=$mold -shared -o $t/d.so $t/c.o $t/b.a -Wl,-exclude-libs=ALL
+readelf --dyn-syms $t/d.so > $t/log
+fgrep -q foo $t/log
+
+echo OK